BitLocker Recovery Keys are all numeric. If you are unable to type letters in the recovery key box, it is because BitLocker recovery keys consist of 48 numbers and do not contain characters. If you are still unable to type in the recovery key box, try pressing the fn+num lock key at the same time. Alternatively, you may be mistaken with Bitlocker’s key code and key id. Your Bitlocker key Id has numbers and letters and Key ID it’s just number.
About how to find Bitlocker recovery key, please refer to:
Hope the information is helpful.
Best Regards,
Hania Lian
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